Method of making wheels with rubberlike treads



l Nv. 4, 1941. v E. AQGRANGE Erm. Y 2,251,465

METHOD OF MAKNG WHEELS WITH RUBBERLIKE TREADS Original Filed Nov. 23,1955 2 Sheets-Sheei; 'l

y l i 'y 10 Y Nov. 4, 1941. E. A. GRANGE E-r Al. 2,251,465

METHOD 0F MAKNG' WHEELS WITH RUBBERLIKE TREADS Original lFiled. Nov. Z,1955 2 Sheets-Sheet 2 Patented Nov. 4, 1941y NITED STATES-PATENT OFFICE.

AMn'rnon or Mama WHEELS wrm nunsnuxs 'ramps Edward A. Grange, AlexanderF. Kaptuller and Erwin J. Schmidt, Chicago, Ill., assignors to .AlliedEngineering Company, Chicago, Ill., a

corporation of Illinois 12 claims. (cree-159.01)

This application is -being led as a division of our prior applicationSerial No. 51,318 led November 23, 1935, now Patent 2,152,684 lof April4, 1939.

Our invention has for its object the provision of a new and improvedmethod of producing wheels of the type set forthv and claimed in theapplication of Er-win J Schmidt, Serial No.

' 700,869 led December 4, 1933', now Patent No.

` its mounting and gripping means shall have such relation to each otherthat the tread member is stretched or expanded circumferentially forits.

preliminary mounting on the supportingl member and is then furtherexpanded circumferentially' and compressed axially by the operation ofmoving the gripping means into their operative holding position, thetread member being given such initial size and shape and othercharacteristics that in the final product the gripped tread member shallbe of the desired size and shape for commercial use without thenecessity for any trimming or other reshaping of the tread member beforeputting the wheel into service. It is another object of our invention toVprovide an improved method of this type whereby the tread member in itsnal gripped form shall be of such changed size and shape as comparedwith its initial size and shape and shall have the points of varyingtension and compression so arranged at the different points about thewheel that the ing and gripping means so as to prevent any creepage ofthe tread member circumferentlally or radially with respect tothemounting. and gripping means. Itis still another object of our inventionto provide an improved method of this type whereby the tread member inthe finished wheel shall be held supported and gripped under tension insuch manner that in the use of the wheel there shall be no permanentdistortion or displacement of the material of the tread member in anydirection as compared with the operative finished wheel conditicn,evenwhen the wheel is subjected to heavy stresses such as characterize theuse vof the device as one of the'supporting wheels on a roller skateworn by a heavy and powerful man` skating and turning corners f sharplyat high speed. It is another object of our invention to provide animproved method of producing a wheel by virtue of which, under thehardest sort of usage, the tread member will wear uniformly about theentire periphery of the wheel without any tendency for the production offlat spots at any points thereabout.

Itis a further object of our invention to provide an improved method ofproducing the type of wheel aforesaid whereby the tread material will begripped tightly and be held securely in position and still be free toyield or flow circumferentially between the supporting and grippingflanges as may be necessary when radial compression of the treadmaterial takes place underr the weight vof the skater, and whereby saidtread material will move backwardly again freely to its normal positionand condition when the radial' pressure' is removed so as to insure thatthere shallbe no .cumulative building up of stretching effects in anypart of the tread material by reason of successive repetitions of theapplication and tread member shall be held firmly by the mountfmaterial.

Another object of our invention is to provide an improved method ofinsuring that the rubber or similar material making up the tread membershall move substantially uniformly so as to ll satisfactorily all partsof the outwardly open circumferentially exte'iding channel between theyflanges as the tread member is placed in position upon the supportingmember and the flangesiare then moved inwardly with respect to eachotherinto their operative gripping position for holding the tread memberexpanded and compressed o its supporting member. 1

It is a further object of our invention to improve methods of the typesdescribed in sundry details hereinafter pointed out. The preferred meansby which we have accomplished our several objects are illustrated in thedrawings and are hereinafter specifically described. That which webelieve to be new and desire to cover by Letters Patent is set forth inthe claims.

In the drawings:

Fig. 1 is a perspective view of the preferred form oi' our completedwheel:

Fig.- 2 is a central vertical sectional view through the wheel of Fig.1;

Fig. 3' is a central vertical sectional view through the sleeve andilanges employed in the arrangement of Fig. 2 for -supporting andgripping the tread member of the wheel, the parts being shown inseparated condition;

Fig. 4 is an edge elevational view of the tread member in its originalshape before expansion and compression, a portion being broken away forclearness of illustration;

Fig. 5 is a view showing the preferred form of means employed forforcing the tread member into position upon the supporting membertherefor, the tready member and supporting member and some of theoperating parts being shown cross section; n

Fig. 6 is a view similar to Fig. 5 but showing the tread member inposition upon the supporting member; A

Fig. 7 is a view showing the preferred form of means employed forpressing the loose flange into position on the supporting member so asto compress the tread member axially and for securing the loose ange inposition, the tread member, the supporting member, the flanges. and someof the operating parts being shown in vertical section; and

Fig. 8 is a view similar to Fig. 'l but showing the parts in theirposition at the close of the operation of securing the loose flange inposition.

Referring now to the several figures of the drawings, in whichcorresponding parts are indicated by the same reference characters, Il)indicates the tread member of our improved wheel as shown in Fig. 1,such tread member being mounted upon a supporting member II which, inthe arrangement shown, is in the form of a sleeve and end iianges I 2and I3, the flange I2 being formed integrally with the sleeve Il as isbest shown in Fig. 3, and the flange I3 being in the form of a washerhaving its opening of a size to iit snugly over the sleeve Il. In thearrangement shown, the flange I3 is secured in position upon the end ofthe sleeve II opposite that. at which the flange I2 is mounted by meansof a rolled over bead portion I 4 oi.' the sleeve II.

In the arrangement shown, the tread member I is originally of a verydiil'erent form from that of the tread member in the completed wheel, asis apparent by a comparison of Figs. 2 and 4 whch are drawn upon thesame scale. The tread member I0 is preferably molded of soft or fiexiblerubber of a quality comparable to that used in the treads of high-gradeautomobile tires and is of a hardness of from 60 to 75 points asindicated by a Shore instrument. We prefer to use rubber of the qualitymentioned and of approximately 68 Shore hardness in our wheels for useon roller skates. As will be readily appreciated from an examination ofthe drawings and particularly Fig. 4, the tread member Ill is in theform of a ring having a tapered opening i axially therethrough, theWalls of the opening being tapered from a true cylindrical form by anangle of approximately 4 at each side of such cylinder. The ring is madesolid in form-that is, with the rubber continuous and of uniformcharacter throughout the member without any divisions between bodyportions at any point.

For the purposes of description, we have considered the tread memberIllas being formed of four portions, a, b, c andfd, formed integrallyits middle transverse plane, the meeting plane of the portions b and c,toward the left or same direction as the taper of the central openingtherethrough. The outer edge faces of the portions a and d are quitesharply tapered, being positioned generally at an angle of from 31 to 32from the transverse planes passing through the substantially parallelends of the tread member, the taper of portion a being in the samedirection as the taper of portionv b while the portion d tapers in theopposite direction. The tread member as shown in Fig. 4 is made for usein a wheel of a certain size and shape designed for a roller skate, thedimensions as indicated on the drawings for the tread and supportingmembers being in correspondence with such designed purposes.

In the arrangement shown, the supporting sleeve II and the flanges I2and Il are preferably made in the form of stampings from sheet metal ofa thickness of .062 inches, the sleeve and flange I2 being formedpreferably from No. 5 dead soft cold rolled strip steel, and the partforming the flange I3 being formed from No'. 2 half hard cold rolledstrip steel. The inner portion of each of the flanges I2 and I3 istapered as shown at an -angle of approximately from the true cylindricalform, while the outer portion of each of the flanges is tapered in thereverse direction at an angle of approximately 45 from cylindrical form.As is shown in Fig. 2, the inner portions of the Aflanges are taperedaway from the sleeve II and are convergently disposed with respect toeach other, while the outer portions of said flanges are tapered towardthe sleeve and are divergently disposed with respect to each other.

As is seen from a comparison of Figs. 3 and 4, which are drawn upon thesame scale, the diameter of the tapered opening through the tread`member I0 in its normal condition, that is to say in its unexpanded anduncompressed condition, is considerably smaller than the outsidediameter of the sleeve II, the diameter of the opening beingapproximately thirteen-eighteenths as great as the outside diameter. ofthe sleeve. As the result, the tread member must be expanded andstretched in order to be placed in position upon the sleeve. Forcarrying out this initial expanding and stretching operation, we employa smooth tapered driftpin I6 having one end portion of a size and shapeto iit the tapered opening I5 in the tread member and having the otherend portion of a size and shape to fit inside the sleeve II, theeffective tapered portion of the driftpin varying from a diametercorresponding to the large end of the opening I5 in the tread member toa diameter corresponding to the outside diameter of the sleeve II, asshown in Fig. 5. For mounting the tread member I0 upon the supportingmember I I, We place the sleeve II in position upon a lug- I'I risingfrom a suitable support I8, and place the larger end of the driftpin I6in position in the upper end of the sleeve with the tread member Ill inposition upon the upper or smaller end of the drftpin. A hollow pressuremember i@ is then forced' downwardly in contact with the dat end of thetreadspember I0 and `to have a working fit in the sleeve II.

' forming the tread member.

that the smaller end of the opening I hasv been expanded to the samesize as that of the larger end of y,said opening. This has the effect ofcutting down the degree of taper of the portion b of the tread member,such portion b as shown in Fig. 6 having been distorted into more nearlycylindrical form than as is shown in Fig. 5. By

reason of the tapered form of the opening I5.V the tread member isenabled to slide smoothly,

into position on the sleeve without objectionable frictional resistancebetween the lead end of the tread member and the sleeve and without anytread member. When the flange I6 is pressed downwardly'into thepositionshown in Figs. 7 and 8, the'tread member I0 is substantiallycompressed axially adjacent the sleeve II and it is compressed to a muchgreater extent at the circumference corresponding to the meeting linesof the oppositely tapered portions of the respective flanges which arespaced outwardly from the sleeve. In the arrangement described, therubber is compressed at the narrowest space between l the flanges toabout three-seventhsof its normal appreciable distortion other than theexpansion as above set forth, the end face and edge face portions of theleading end of the tread member retaining substantially their normalconfiguration.

For compressing the tread member I0 axially and expanding itadditionally diametrically, an arrangement somewhat similar to thatshown in Fig. 5 is used, comprising a supporting member 20 having a seatto. receive the outer face of the flange I2 and a lug 2| risingtherefrom of a size When it is desired to' compress the tread member,the sleeve II and tread-member Il] thereon are placed in position uponthe support 20 and the lug 2|, and the washerwl is placed in operativeposition on the upper or top end face of the tread member. A. pressuresleeve 22 is then brought down into nesting arrangement with the washerI3 y andl power is applied for pressing the washer vmember II betweenthe anges I2 and I3 under pressure suiiicient to prevent any creepageofthe tread member circumferentially or radially relative to its holdingmeans under the severest stresses the wheel can be put to in ordinaryuse and yet not great enough to damage the material We have found apressure ranging from about 300 lbs. to about 700 lbs, per square inchto be satisfactory.- With rubber of the type mentioned aboveand of aShore hardness of approximately 68 points, we prefer a pressure ofapproximately 5 00 lbs. per square inch.

As is best indicated in Fig. i6, the parts are line of junction betweenthe straight end face and the tapered edge face of the portion d of thetread member. In the same way, when the flange I3 is in position, theline of junction of its oppositely tapered portions stands substantiallyopposite the line markingthe separation of the flat end from the taperededge of the portion a of the width. The compression of the inner ormounting portion of the tread member axially between the anges causesthe rubber making up the tread member to expand circumferentially anddiametrically to a considerable extent, the straight outer end faces ofthe portions a and d being forced inwardly toward each other with theresult that the tapered edge faces of said portions are brought intoapproximately transverse planes. The -inal shape of the tread member inthe wheel, therefore. is radically different from that of the treadmember as originally formed and before being mounted in place.

By the use of our improved method by which the opening through the treadmember is given a tapered formand by which the edge portions of themember are `given a predetermined differential form and shape all byproducing inexpensively the member in a mold having a. cavity of theshape of the tread member shown in Fig. 4, we are enabled to produce awheel substantially symmetrical, as shown in Figs. 1, 2 and 8of such form, shape and arrangement that-it is suitable for commercial use as itcomes from the press and Without 'any trimming or other costly re-.shaping operations, which, it will be appreciated,

is a matter of tremendous importance in the manufacture of an articleused in such'great quantities as wheels of the kind and type inquestion.

By the use of our improved arrangement of partsmaking up the wheel andthe means for producing the wheel according to our improved method, wehave produced a structure in which the tread member is held securely inposition by I the combination of stresses and compressive forces. 'Ihetread member is held strongly against movement circumferentially withrespect tothe sleeve II and against movement radially outwardly withrespect tothe flanges I2 and I3. i

'I'he outer tapered or divergent portions of the flanges serve assupports for holding the outer, exposed free portion of the tread memberagainst undue movement transversely. Notwithstanding the secure mountingof Athe tread member with respect to undesired movements, the treadmember is free to yield inwardly without the necessity for theapplication of great pressure for effecting suchyielding movement. Byreason of the tread member being gripped and held in position .by theuse of an outwardly open, circumferor rough surfaces. The wheels take avelvetlike grip upon the skating surface even when such surface is quitesmooth, no appreciable slippage of the wheels on the skating surfacetaking place due to the skater turning sharp corners at high speeds ormaking quick stops. Our improved wheels operate silently, the wheels inrolling contact with a sidewalk or other skating surface under allordinary skating conditions creating no noticeable sound. The life ofour improved wheel under severe service conditions has been found to bemany times greater than that of the ordinary type of steel skate wheeloperating under less severe conditions.

While we have illustrated in detail and have specically described awheel of a certain construction and of a certain'size for use-inparticular on roller skates, it is to be understood that such has beendone merely for the purposes of illustrating the principles of,ourinvention and teaching those skilled in the art how to produce,

shape and size that at the end of the voperatimis of expansion andcompression the tread member shall have a substantially symmetrical formsuitable for use commercially without reshaping.

3.l The method of making a wheel of the type described which comprisesthe steps of mounting a circular tread member of soft rubber-likematerial having a circular opening therethrough upon a supporting memberof substantially cylindrical form and of substantially greater externaldiameter than the diameter `of said opening by according to ourinvention, wheels for widely different uses and differing materially inshape and size. We wish it to be understood also that our invention isnot limited to the particular arrangements and the particular methodsillustrated and described as we recognize that changes may be madetherein without departing from the principles of the invention,

We claim:

1. The method of making a wheel of the type described which comprisesthe steps of mounting a. circular tread member of soft rubber-likematerial having a circular opening therethrough upon a supporting memberof substantially cylindrical form and of substantially greater externaldiameter than the diameter of said opening by expanding the tread memberto an internal diameter at least as great as the outside diameter of thesupporting member and positioning the tread member on the supportingmember, and then securing the tread member on the supporting' memberbetween holding elements in substantially changed form and insubstantially compressed condition axially by shortening the distancebetween the holding elements while maintaining the holding elements andthe tread member in thesame rotative relation about their axes,

and the preliminary step of giving the tread member such predeterminedshape and size that at the end of the operations of expansion andcompression the tread member shall have a substantially symmetrical formsuitable for use commercially without reshaping.

. 2. The method of making a wheel of the type described which comprisesthe steps of mounting a circular tread member of soft rubber-likematerial having a circular opening therethrough upon a supporting memberof substantially cylinrlrical form and of substantially greater externaldiameter than the diameter of said opening by expanding the tread memberto lan internal diameter at least as great as the outside diameter ofthe supporting member and positioning the tread member on the supportingmember, and then securing the tread member on the supporting memberbetween holding elements in substantially changed form and .insubstantially greater expanded condition diametrically and insubstantially compressed condition axially by shortening the distancebetween the holding elements while maintaining the holding `elements andthe tread member in the same rotative relation about their axesfl andthe preliminary step of giving the tread member such predeterminedsliding the tread member along a tapered driftpin into position on thesupporting member, and then securing the tread member on the supportingmember between holding elements in substantially changed form and insubstantially .compressed condition axialiy by shortening the have asubstantially symmetrical form suitable for use commercially withoutreshaping.

4. The method of making a wheel of the type described which comprisesthe steps of mounting a circular tread member of soft rubber-likematerial having a circular opening therethrough upon a supporting memberof substantially cylindrical form and of substantially greater externaldiameter than the diameter of said opening by sliding the tread memberalong a tapered driftpin into position on the supporting member, andthen securing the tread member on the supporting member between holdingelements in substantially greater expanded condition diametrically andin substantially compressed condition axially by shortening the distancebetween the holding elements while maintaining the holding elements andthe tread member in the same rotative relation about their axes, and thepreliminary step of giving the tread member such predetermined shape andsize that at the end of the operations of expansion` and compression thetread member shall have a substantially symmetrical form suitable foruse commercially without reshaping.

5. The method of making a wheel which'comprises the utilizationof acircular tread member of soft rubber-like material having an openingaxially therethrough and having straight end face portions adjacent theopening substantially at rightangles to the axis of the tread member andtapered end face' portions adjacent the periphery of the tread member,expanding and mounting said tread member upon a supporting member ofsubstantially cylindrical form and of substantially greater externaldiameter than the diameter of said opening, and then securing the treadmember on the supporting member between holding elements insubstantially changed form axially therethrough and having straight endface portions adjacent the opening substantially at right angles totheaxis ofthe tread member and ltapered end face portions adjacent theperiphery of the tread member, expanding and mounting said tread memberupon a supporting member of substantially cylindrical form and of.substantially greater external diameter than the 7. The method of makinga wheel which com-y prises the utilization of a circular tread member ofsoft rubber-like material tapered from about its middle transverse planetoward one end and having an opening axially therethrough, stretchingsaid tread member for forcing it into position cn a substantiallyover-sized supporting member with a greater degree of expansion at thesmaller end of the tread'member than at the other end, and then securingthe tread member between holding elementsy on the supporting member insubstantially changed form and in substantially compressed conditionaxially by shortening the distance between the holding elements Whilemaintaining the holding elements and the tread member in the samerotative relation about their axes.

8. The method of making a wheel which comprises the utilization of acircular tread member of soft rubber-like material tapered from aboutits middle transverse plane toward one end and having an opening axiallytherethrough also tapered toward the same end, stretching said treadmember for forcing it into position on a supporting member ofsubstantially cylindrical form and of substantially greater externaldiameter than the diameter of said opening at its smaller end with agreater degree of expansion at the smaller end of the tread member thanat 4the other end, and then securing the tread mem- 9. In the hereindescribed method of making a wheel of the type described, those stepswhich comprise tapering from its leading end the internal walls of 'anannular tread member of soft rubber-like material, and then expandingand slidably mounting the tread member on a supporting member ofsubstantially cylindrical form and of substantially greater externaldiameter than the diameter of said opening at its smaller comprisetapering from its leading end at an angle of approximately 4 withrespect to its axis the internal walls of an annular tread member ofsoft rubber-like material, and then expanding and lslidably mounting thetread memberv on a supporting member of substantially cylindrical formand of an external diameter substantially greater than 'the smaller endof they tapered opening in the tread member whereby the frictionalresistance between the two members is such that the face portions of theleading end of the tread member are maintained in substantially theirnormal configuration.

1l. The method of making a wheel of the vtype described which comprisesthe steps of mounting a circular tread member of soft rubber-likematerial having a circular 'opening therethrough expandingthe treadmember to an internal diameter at least as great as the outside diameterof the supporting member and positioning the tread member on thesupporting member, and then securing the tread member on the supportingmember in substantially changed form and in substantially compressedcondition axially between holding elements by shortening the distancebetween the holding elements while maintaining the holding elements andthe tread member in the same rotative relation about their axes, theinner portions of the inside faces of said elements being c-onvergentlydisposed with respect to each other and the outer portions of the insidefaces of the elements being divergently disposed with respect to eachother as viewed in cross section from the wheel axis, and thepreliminary step of giving the tread member such predetermined shape andsize that at the end of the operations of expansion and compression thetreadv member shall have a substantially symmetrical form suitableforuse commercially without reshaping.

12. 'I'he method of making a wheel which comprises the utilization of acircular tread member of soft rubber-like material having an openingaxially therethrough and having straight end face portions adiacent theopening substantially at right angles to the axis of the tread memberand tapered end face portions adjacent the periphery of the treadmember, expanding and mounting said tread member upon a supportingmember of substantially cylindrical form and of substantially greaterexternal diameter than the diameter of said opening, and then securingthe tread member on the supporting member in substantially changed formand in substantially compressed condition axially at the portionadjacent the supporting member between holding elements by shorteningthe distance between the holding elements while maintaining the holdingelements and the tread member in the same rotative relation about theiraxes. the inner portions of the inside faces of said elements beingconvergently disposed with respect to each other and the outer portionsof the inside faces of the elements being divergently disposed withrespect to each other as viewed in cross section from the wheel axis, soas to make said tapered end face portions of the tread member conformapproximately to transverse planes.

EDWARD A. GRANGE.

ERWIN J. SCHMIDT.

